comparison of the effects of melatonin and midazolam on hemodynamic status in patients candidate for cataract surgery: a randomized controlled clinical trial

Introduction: maintaining hemodynamic stability during cataract surgery is crucial, particularly in elderly patients or those with underlying medical conditions. melatonin and midazolam are among the medications used for sedation and improving intraoperative conditions; however, they may have different effects on hemodynamic parameters. this study aimed to compare the impact of these two medications on hemodynamic status before, during, and after cataract surgery. methods: this clinical trial was conducted on 40 patients scheduled for cataract surgery under general anesthesia. participants were randomly assigned to one of two intervention groups; one of which received 0.1 mg/kg of oral melatonin, while the other received 70–80 µg/kg of intravenous midazolam. both administrations occurred 1 h before surgery. a saadat monitor was used to record hemodynamic parameters, namely systolic blood pressure (sbp), diastolic blood pressure (dbp), and heart rate (hr), at three intervals: 30 min before the operation, during the operation, and 6 h after the operation. statistical analysis was performed in spss software (version 26), employing a significance threshold of p < 0.05. results: analysis indicated that hemodynamic parameters, including sbp, dbp, and hr, were comparable between the two groups before, during, and after the operation, with no statistically significant intergroup differences (p > 0.05). in contrast, a significant intragroup change was observed in the melatonin group regarding hr over time (p = 0.005). conclusion: although both medications were effective in maintaining hemodynamic stability, melatonin resulted in better stability of hr after surgery, compared to midazolam. therefore, given its fewer side effects and efficacy on regulating hr, melatonin could be considered a safer alternative for patients prone to tachycardia in cataract surgery.